


Short "Assistant"

by saturnwonder



Category: Undertale (Video Game)
Genre: F/M, Frisk is over 18+, Gaster gonna dick her good, Pet Names, Starts One Sided, caressing, cursing, female/male - Freeform
Language: English
Status: In-Progress
Published: 2018-12-15
Updated: 2018-12-15
Packaged: 2019-09-19 15:49:16
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,260
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17004540
Author URL: https://archiveofourown.org/users/saturnwonder/pseuds/saturnwonder
Summary: When monsters escaped the Underground they started getting their memories back about those who were lost to the void. They were like wisps of fogginess, but memories all the same. Those and Frisk's encounter with the monster during her trek in the Underground were enough to convince both Sans and Alphys to start researching into saving the previous Royal Scientist. What happens after his rescue is something Gaster didn't see coming.





	Short "Assistant"

**Author's Note:**

> Howdy everyone! Gonna put this out there right away but I currently don't see this being continued anytime soon. This story is based on the doodle dumps of determinedvoid on Tumblr, but due to the Tumblr purge, I don't know if I will want to continue this or not. This chapter consists of the 3 (and so far only) posts I made on Tumblr.
> 
> Their work is just so inspiring! I love the dynamic that they have between Frisk and Gaster that I was first overwhelmed with giddiness and admiration! I still am of their work, but these doodle dumps were what caught my eye. I'll try and save their work so, if I do come back to this, I'll have their original pieces to get inspiration from.
> 
> Please mind the tags, and hope to see you on the flip side!!

Many years passed after Gaster was released from the Void and when he first walked out of the machine with the monsters who fell in with him he was bombarded by Sans and Papyrus. Like the other families of those who were lost they were truly happy to have him back. Miraculously, when they escaped the Underground, monsters started getting their memories back about those who were lost to the void due to the core accident. They were like wisps of fogginess, but memories all the same. Those and Frisk's encounter with the monster during her trek in the Underground were enough to convince both Sans and Alphys to start researching into saving the previous Royal Scientist.

By the time Gaster and the others were saved, Frisk had grown into a remarkable young woman. She had not only graduated college at an early age but she had shown interests in the scientific community, working alongside Sans and Alphys on the equations and necessary components needed to get Sans’ machine in their Snowdin basement running. Realizing her potential Gaster immediately invited Frisk to be a part of his newest team of personal scientists, next to Sans and Alphys, and together the four of them made breakthroughs in the main three branches of science: Physical, Earth, and Life. Frisk and Gaster made multiple of their own, together, in physical science, as it contains their interests with physics and chemistry (Sans decided earlier on he would focus more on his love for astronomy). Over the following months, they didn’t realize that love would step into their lives.

Brushes of the other's arm would send shivers up their spine, the warmth they would feel being pressed close to attach an engine or when they were arguing excitedly with the other at the whiteboard, their laugh during the horrible jokes they told each other, and the loving gazes they never saw each other giving them. Everyone knew; it was clear as day, but these two were so dense about the other’s feelings that it would aggravate everyone in the room to the point of frustration. Even Alphys, who loved the long drawn out romantic way these relationships would go, was getting impatient.

It was near a years time from joining Gaster’s personal team. Frisk was alone in the lab, having volunteered to do clean up from one of her newest completed experiments with Gaster, who had decided to retire to his private chambers in the higher levels of his company. The scientist practically lived in the labs Underground, so Frisk suggested the doctor have a chamber to sleep and change for overnight experiments. She didn’t like how Gaster would run himself ragged, so to keep him from exhausting himself she proposed the idea during one of their daily meetings. Everyone agreed and his team was also allowed a room of their own, for the same reasons of course.

After that, the two had grown far too close for either to not notice their own affections for the other, and it left them feeling tired and worn by the end of each day. Being in such close proximity, gentle brushes of their arms, their intent focus as the other stays determined, their smile… it was becoming too much, and yet they had no idea still of how the one they lusted after felt.

Gaster was in desperate need to get out of the near-abandoned room to retreat to his private quarters. Watching the way Frisk was moving about, listening to music on her iPod, her hips swaying gently before jerking to the beat left his SOUL burning and his breath stolen. Gods she was going to be the dusting of him.

He could never tell her though, never let her know of his deepest desires to throw her over his bed and ravage her like the sublime creature she was. He knew of her accomplishments in the UnderGround, how strong and fearless she was, and it inspired him to want to seek her glance at every moment. He needed her. Craved her. He needed a cold shower.

20 minutes later he re-emerged into the lab, his favorite robe wrapped around his firm form, half expecting Frisk to be gone when he stopped short in the doorway. She was bent over another experiment, her lab coat thrown haphazardly over her back, hips still moving to the upbeat song playing. He thought he could beat this intense heat but it only grew into a burning inferno, not realizing how quickly he crossed the room to grab Frisk by her arms.

Frisk screamed in surprise, though that fear quickly dissipated when she realized who had grabbed her, her heart beating erratically from her surprise and lust for the monster. He pulled her body flush to his own to nuzzle into her neck as his hand came up to steady her head by her chin.

“Wait, Mr. Gaster! Auughh!”

I must have her.

Frisk wasn’t sure what had gotten into her boss… But She Loved It.

Sure, she had been craving for his attention in this exact manner for quite some time, dreaming of Gaster coming to her like this and him having his way with her, but she hadn’t thought of how desperately she needed the way his hands stroked her neck or the way he nuzzled his face against her cheek, his breath sending jolts of arousal down her spine.

Gaster’s hands moved down, gliding over her shoulders to slip her lab coat off to reveal the tank top she wore underneath. Frisk held her voice in, biting her lower lip in an attempt to silence herself. She didn’t want to act like she wanted Gaster to throw her against the closest wall to have his way with her. She needed to control herself, and as the coat fabric fell into a pile on the floor Frisk turned to stare at the tall monster over her shoulder, those bright, brown eyes half-lidded in affection. She couldn’t deny how badly she wanted the senior scientist.

A silent gasp, Gaster was back on her, caressing her middle as a hand slowly inched back up towards her throat. He peppered her exposed flesh with kisses, short bursts that drove him wild, increasing his desire for her. Frisk moaned his name and it spurred him on, gripping her shirt as she leaned back against him, losing himself in the sensual way her body shook as he ran his tongue over her heated skin.

“Ah, ah Gaster… please…”

Something snapped in him as he came back to his senses, Gaster pushing away from Frisk as if burned, panic in his eyes, and he was quick to cover his face in shame. He had taken advantage of his colleague, his protege, the girl of his wildest fantasies, and she hadn’t even consented let alone tell him she even wanted him…

Damnit damnit damnit, this is beyond terrible.

“What have I done? Oh, my stars I didn’t mean to go this far! Ms. Frisk, please forgive me, I didn’t mean to behave so vulgarly to you. There is no excuse for what I’ve done…” He’s shaking, so disgusted with himself and how he tried taking advantage of her. Adjusting his robe he quickly gathered her jacket from the floor, Frisk standing calmly behind, surprised to find the fabric suddenly laid over her shoulders like a blanket. Gaster pulled her collar closed, a sigh escaping his nasal cavity. He needed to make this right, “Allow me to get dressed. I’ll take you home right now…”

“NO!”

**Author's Note:**

> Let me know if I should continue or not :3


End file.
